Locking mechanism for cabinets, instrument cases, and the like



June 13, 1950 c. w. FISCHER LOCKING MECHANISM FOR CABINETS, INSTRUMENTCASES, AND THE LIKE Filed Feb. 20, 1947- INVENTOR. QZI'ZWfAfC/Z BY 7% yW Patented June 13, 1950 LOCKING.MECHANISM. FOR CABINETS, INSTRUMENTCASES, AND, THE LIKE Carl W. Fischer, Chicago, 11]., assignorto The.

Powers Regulator Company, Chicago, 111,, a cor-,

porati nof l nois Application February 20, 19417, SerialNo. 729,786

fi-Clairns. 1

This invention pertains to locking mechanism for cabinets, instrumentcases and the like.

An object of the invention is to provide a looking mechanism which isparticularly suited for cabinets and the like.

Another object is to provide a lock which does not have any exteriorprotrusionswhen the door is locked.

A further object is to provide a lock which is relatively inconspicuouswhen viewed from the outside of the door.

Another object is to. provide a locking mechanism wherein the latch ispositively held in latched position as distinguished from the usual typewherein the latching position is maintained by a spring.

A further object is to provide a locking mechanism having a cam actionwhich has suflicient mechanical advantage between the lock and cam tocompress a door gasket tightly.

Another object is to provide a locking mechanism which is readilyadaptable to compensate for door gaskets of varying. thickness.

A further object is toprovidea locking mechanism wherein the movement ofthe latch from. locked to unlocked position is spring actuated.

With these and various other objects in view, the invention mayconsistof certain novel. fea-.. tures of construction and operation, aswillbe more fullydescribed and particularly pointed outin thespecification, drawing and claims appended hereto.

In the drawings, which illustrate an embodiment of the device andwherein like. reference characters are used to designate likeparts:

Figure 1 is a frontelevation of a locking mechanism embodying theinvention, asviewed from the outside-of a door in lockedposition.T-heportions of the device positioned behind thedoor are. shown inbroken lines;

Figure 2 is a side elevation, partially incrossv section, of thedevicein locked-position;

Figure 3 is a rear elevation of the lockingmechanism inlockedpositionthesame looking toward the left as viewed in Figure 2;and;

Figure 4 is. a transverse sectional elevation of the the plungerandslide-pin taken through the disclosed in Jacobi Patent No. 2,086,034,issued July-6, 1937. When a key isinserted-inthe key hole l8, and turned"teunlock theunit, thehead" 2. or push. button 20:. may then. be pushedinwardly causing thebolt or pivotedpin engaging member- 22. to moveupwardly to. engage slide or locking pin 24;

Theplunger 26 is mounted adjacent-and above the lock unit and isprovided with. a push button. head 28. The housing 29 0f. the lockingunitand the housing 3i: of the plunger may be in-. tegrally formed orotherwise securedv adjacent each other inthe.relationshipshown inthedrawings, or they may beseparately mounted. in the door. The slide pin24 is mountedin the plunger 26 adjacent the inside. end. thereof. Theplunger 26 is provided-witha chamber 21 in which is. mounted thecoilspring-.30, one end of: which is. secured to the stop engaging; slidepin- 2.4 by

the. set screw 32; the. end. of the spring being inserted in a,longitudinal slot-33 inthe-pin, and: the set screw holding itagainsttheend; of the slot. The, other end of: the spring is seatedagainst-theside of Chamber 21: The spring 30.. urges the pin 240utward1yof the plunger and toward, the. bolt 22, The plunger housing 3;! isprovided with a longitudinal channel 3,4 for ac commodating the outerend oflthe pin 2!! when it, is sliding between, locking and: unlockingpositions. On either side of: the channel, 34; at the endof" the housingare'lugs 36 whichkeep the. pin 24; in alignment with channel; 34 whenthe. latter is. extended from the plungen inlocked position as shown inFigure 2 in which position the pin 24 engages the inner end of housing3.!- between lugs 36; which pin engaging surface forms stop 31.

The upper-side of the plunger housing- 31-. is,

provided with a, longitudinal. s10 t;.38, for receiving the screw 32when the. plunges-26. is moving toward the left as viewed in Figurez.The springplunger, thereby urging the latter outwardly towardunlockedposition. The inner endofthe plunger is provided with an adjustingscrew4 3i A. latching. lever 46 ismivotally securedtothe door. frame-at; Theupper endgof the lever curved=d0wnwardly to hookover the pinor keeper.5!] when themeohanism is in locked: position, thepin engagingsurfacethereof having a cam face 58. The pin 501is-secured to thedoorandis in the same.- horizontal plane. as the pivot;

screw, 48: A tension. spring 52' has. one end: hooked to the upper endof thelever Mizand the other end is attached to the pin 54 on the doorframe [4. The spring tends to lift the upper end of the lever 46upwardly, urging it into unlatched position. A stop pin 56 on the doorframe limits the upward movement of the upper end of the lever.

In operation, to open the door l2 which pivots on hinges not shown, akey is inserted in the key hole [8 and turned to unlocked position. Thepush button head 20 of the lock unit I6 is then pushed inwardly, whichcauses the bolt 22 to move upwardly, engaging the slide pin 24 andmoving it upwardly into the plunger 26, so that it disengages the stop31 at the end of casing 3i and compresses spring 30. When the end ofslide pin 24 has been pushed inwardly beyond the end of the casing, itwill be in a position to enter the channel 34. The plunger is then freeto be moved outwardly by the lower end of the latching lever 46. Theupper end of lever 46 is pulled upwardly by spring 52, thereby movingthe cammed face 58 of the lever from in front of the pin 50. At the sametime the lower end of the lever which engages the adjusting screw 44pushes the plunger 26 outwardly until the slide pin 24 reaches the endof channel 34, which acts as a stop. The movement of the lever 46 islimited by the upper end engaging the stop pin 56. The pressure of thelower end of the lever against the plunger will impart an openingimpetus to the door after the upper end 58 has moved from in front ofthe pin 50.

To close and lock the door l2, pressure is placed on the push buttonhead 28 of the plunger 29 to move the door toward closed position. Thepressure of spring 40 against the plunger tending to hold it outwardlyin unlocked position is sufficient so that the door may be moved to aclosed position without appreciably moving the plunger inwardly.Continued pressure on push button 28 after the door has reached closedposition, moves the plunger inwardly and the adjusting screw 44 engagesthe lower end of lever 46, and causes the upper hooked end 56 to moveinto locking engagement with pin 50 as shown in Figure 2. Slide pin 24moves to the end of channel 34 and then is pushed outwardly by spring30. The pin 24 is then in engagement with stop 3'! at the end of housing3| which acts to prevent the plunger 26 from being moved outwardly.

As previously pointed out the pivot point 48 of the lever 46 is in thesame horizontal plane as the pin 50 with the result that there is aneven distribution of the pull between the parts. This is particularlyimportant where there is a gasket or sealing element between the doorand frame as there is considerable leverage exerted to compress thegasket when the plunger is pushed inwardly against the lower end oflever 46. The camming action of the under face 58 of the hooked portionof the upper end of lever 46 on the pin 50 draws the door tightlyclosed. The adjusting screw 44 may be screwed inwardly to shorten theoverall length of the plunger 26, consequently the lower end of lever 46will not be moved as much when the plunger is in locked position and thecam face 58 of the upper end of the lever will not be moved as far downagainst pin 58, thereby lessening the pressure of the door against thegasket. Where the gasket has become worn, or to compensate fordifferences in sizes of gaskets, the adjusting screw 44 may be screwedoutwardly with the result that the downward movement of the cam face 58against pin 50 will be increased.

While the lock unit I6 is described as being key operated it is obviousthat a push button unit which does not require a key could be used inplace of the key operated unit.

It is to be understood that I do not wish to be limited by the exactembodiment of the device shown, which is merely by way of illustrationand not limitation, as various and other forms of the device will, ofcourse, be apparent to those skilled in the art without departing fromthe spirit of the invention or the scope of the claims.

I claim:

1. In combination with a closure and frame therefor, a keeper on saidclosure, locking mechanism for the closure comprising a latching memberpivotally mounted on said frame and adapted to engage said keeper onsaid closure, resilient means biasing said latching member towardunlatched position, a housing mounted on said closure having an openingleading to the exterior thereof, means slidably extending through saidopening and housing and interengaging with said latching member formoving the latching member to latched position, means for locking saidlatching member in said latched position, said third named meansincluding releasable means carried by said second named means andengageable with the end of said housing to hold said second named meansin locking relation to said latching member, resilient means urging saidsecond named means toward unlatched position, and means carried by saidclosure and actuatable from the exterior thereof and engageable withsaid releasable means for disengaging the same from the end of thehousing, whereby said last named resilient means actuates said secondnamed means to unlatched position and said first named resilient meansactuates said latching member to unlatched position.

2. In combination with a closure and frame therefor, a keeper on saidclosure, locking mechanism for the closure comprising a latching memberpivotally mounted on said frame having one leg provided with a lockingcam adapted to engage said keeper, and another leg being adapted to bemoved to move said first named leg, resilient means biasing saidlatching member toward unlatched position, a housing mounted on saidclosure having an opening leading to the exterior thereof, meansslidably extending through said opening and housing and interengagingwith the second named leg of said latching member for moving thelatching member to latched position,

. said second named means including a plunger slidably mounted in saidhousing and having one end engageable with the second named leg of saidlatching member, a locking pin provided on said plunger engageable withsaid housing to maintain said plunger in latched position, resilientmeans urging said pin toward latched position, resilient means urgingsaid plunger toward unlatched position, and a bolt carried by saidclosure and actuatable from the exterior thereof for moving said pin toinoperative position whereby said last named resilient means actuatessaid plunger to inoperative position and said first named resilientmeans actuates said latching member to unlatched position.

3. In combination with a closure and frame therefor, a keeper on saidclosure, locking mechanism for the closure comprising a latching memberpivotally mounted on said frame having one leg provided with a lockingcam adapted to engage said keeper, and another leg being adapted to bemoved to move said first named le resilient means biasing said latchingmember toward unlatched position, a housing mounted on said closurehaving an opening leading to the exterior thereof, means slidablyextending through said opening and housing and interengaging with thesecond named leg of said latching member for moving the latching memberto latched position, said second named means including a plungerslidably mounted in said housing and having one end engageable with thesecond named leg of said latching member, a locking pin provided on saidplunger engageable with said housing to maintain said plunger in latchedposition, resilient means urging said pin toward latched position,resilient means urging said plunger toward unlatched position, and abolt carried by said closure and actuatable from the exterior thereoffor moving said pin to inoperative position whereby said last namedresilient means actuates said plunger to inoperative position and saidfirst named resilient means actuates said latching member to unlatchedposition, said housing having a portion for receiving said pin when saidplunger is in inoperative position and for maintaining said pin ininoperative position.

4. In combination with a closure and frame therefor, a keeper on saidclosure, locking mechanism for the closure comprising a latching memberpivotally mounted on said frame having one leg provided with a lockingcam adapted to engage said keeper, and another leg being adapted to bemoved to move said first named leg, resilient means biasing saidlatching member toward unlatched position, a housing mounted on saidclosure having an opening leading to the exterior thereof, meansslidably extending through said opening and housing and interengagingwith the second named leg of said latching member for moving thelatching member to latched position, said second named means including aplunger slidably mounted in said housing and having one end engageablewith the second named leg of said latching member, a locking pin betweensaid plunger and housing to maintain said plunger in latched position,resilient means urging said pin toward latched position, resilient meansurging said plunger toward unlatched position, and a bolt carried bysaid closure and actuatable from the exterior thereof for moving saidpin to inoperative position whereby said last named resilient meansactuates said plunger t inoperative position and said first namedresilient mean actuates said latching member to unlatched position.

5. In combination with a closure and frame therefor, a keeper on saidclosure, locking mechanism for the closure comprising a latching memberpivotally mounted on said frame and adapted to engage said keeper onsaid closure, resilient means biasing said latching member towardunlatched position, a housing mounted on said closure having an openingleading to the exterior thereof, means slidably extending through saidopening and housing and interengaging with said latching member formoving the latching member to latched position, means for locking saidlatching member in said latched position, said third named meansincluding releasable means carried by said second named means andengageable with the end of said housing to hold said second named meansin locking relation to said latching member, resilient means urging saidsecond named means toward unlatched position, and means carried by saidclosure and actuatable from the exterior thereof and engageable withsaid releasable means for disengaging the same from the end of thehousing, whereby said last named resilient means actuates said secondnamed means to unlatched position and said first named resilient meansactuates said latching member to unlatched position, said housing havinga portion for receiving said pin when said plunger is in inoperativeposition and for maintaining said pin in inoperative position.

6. In combination with a closure and frame therefor, a keeper on saidclosure, locking mechanism for the closure comprising a latching memberpivotally mounted on said frame and adapted to engage said keeper onsaid closure, resilient means biasing said latching member towardunlatched position, a housing mounted on said closure having an openingleading to the exterior thereof, means slidably extending through saidopening and housing and interengaging with said latching member formoving the latching member to latched position, means for lockin saidlatching member in said latched position, said third named meansincluding releasable means between said second named means and housingmovable to hold said second named means in locking relation to saidlatching member, resilient means urging said second named means towardunlatched position, and means carried by said closure and actuatablefrom the exterior thereof and engageable with said releasable means formoving the same to inoperative position whereby said last namedresilient means actuates said second named means to unlatched positionand said first named resilient means actuates said latching member tounlatched position.

CARL W. FISCHER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 613,356 Conerly Nov. 1, 1898938,114 Boettcher Oct. 26, 1909 1,302,063 Malone Apr. 29, 1919 1,864,956Stone June 28, 1932' 2,083,963 Ruggiero June 15, 1937 2,156,004Vanderlinde Apr. 25, 1939 2,218,183 Springer Oct. 15, 1940

